Selective TRPA1 channel blocker (IC50 values are 67 and 289 nM at human and rat TRPA1 receptors respectively). Displays 1000-fold selectivity for TRPA1 over other TRP channels, and is >150-fold selective over 75 other ion channels, enzymes and G-protein-coupled receptors. Exhibits analgesic effects in a rat osteoarthritic pain model. Purity 98%. MW (observed): 207.24